1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * device.h - generic, centralized driver model
4 *
5 * Copyright (c) 2001-2003 Patrick Mochel <mochel@osdl.org>
6 * Copyright (c) 2004-2009 Greg Kroah-Hartman <gregkh@suse.de>
7 * Copyright (c) 2008-2009 Novell Inc.
8 *
9 * See Documentation/driver-api/driver-model/ for more information.
10 */
11
12 #ifndef _DEVICE_H_
13 #define _DEVICE_H_
14
15 #include <linux/dev_printk.h>
16 #include <linux/energy_model.h>
17 #include <linux/ioport.h>
18 #include <linux/kobject.h>
19 #include <linux/klist.h>
20 #include <linux/list.h>
21 #include <linux/lockdep.h>
22 #include <linux/compiler.h>
23 #include <linux/types.h>
24 #include <linux/mutex.h>
25 #include <linux/pm.h>
26 #include <linux/atomic.h>
27 #include <linux/uidgid.h>
28 #include <linux/gfp.h>
29 #include <linux/device/bus.h>
30 #include <linux/device/class.h>
31 #include <linux/device/devres.h>
32 #include <linux/device/driver.h>
33 #include <linux/cleanup.h>
34 #include <asm/device.h>
35
36 struct device;
37 struct device_private;
38 struct device_driver;
39 struct driver_private;
40 struct module;
41 struct class;
42 struct subsys_private;
43 struct device_node;
44 struct fwnode_handle;
45 struct iommu_group;
46 struct dev_pin_info;
47 struct dev_iommu;
48 struct msi_device_data;
49
50 /**
51 * struct subsys_interface - interfaces to device functions
52 * @name: name of the device function
53 * @subsys: subsystem of the devices to attach to
54 * @node: the list of functions registered at the subsystem
55 * @add_dev: device hookup to device function handler
56 * @remove_dev: device hookup to device function handler
57 *
58 * Simple interfaces attached to a subsystem. Multiple interfaces can
59 * attach to a subsystem and its devices. Unlike drivers, they do not
60 * exclusively claim or control devices. Interfaces usually represent
61 * a specific functionality of a subsystem/class of devices.
62 */
63 struct subsys_interface {
64 const char *name;
65 const struct bus_type *subsys;
66 struct list_head node;
67 int (*add_dev)(struct device *dev, struct subsys_interface *sif);
68 void (*remove_dev)(struct device *dev, struct subsys_interface *sif);
69 };
70
71 int subsys_interface_register(struct subsys_interface *sif);
72 void subsys_interface_unregister(struct subsys_interface *sif);
73
74 int subsys_system_register(const struct bus_type *subsys,
75 const struct attribute_group **groups);
76 int subsys_virtual_register(const struct bus_type *subsys,
77 const struct attribute_group **groups);
78
79 /*
80 * The type of device, "struct device" is embedded in. A class
81 * or bus can contain devices of different types
82 * like "partitions" and "disks", "mouse" and "event".
83 * This identifies the device type and carries type-specific
84 * information, equivalent to the kobj_type of a kobject.
85 * If "name" is specified, the uevent will contain it in
86 * the DEVTYPE variable.
87 */
88 struct device_type {
89 const char *name;
90 const struct attribute_group **groups;
91 int (*uevent)(const struct device *dev, struct kobj_uevent_env *env);
92 char *(*devnode)(const struct device *dev, umode_t *mode,
93 kuid_t *uid, kgid_t *gid);
94 void (*release)(struct device *dev);
95
96 const struct dev_pm_ops *pm;
97 };
98
99 /**
100 * struct device_attribute - Interface for exporting device attributes.
101 * @attr: sysfs attribute definition.
102 * @show: Show handler.
103 * @store: Store handler.
104 */
105 struct device_attribute {
106 struct attribute attr;
107 ssize_t (*show)(struct device *dev, struct device_attribute *attr,
108 char *buf);
109 ssize_t (*store)(struct device *dev, struct device_attribute *attr,
110 const char *buf, size_t count);
111 };
112
113 /**
114 * struct dev_ext_attribute - Exported device attribute with extra context.
115 * @attr: Exported device attribute.
116 * @var: Pointer to context.
117 */
118 struct dev_ext_attribute {
119 struct device_attribute attr;
120 void *var;
121 };
122
123 ssize_t device_show_ulong(struct device *dev, struct device_attribute *attr,
124 char *buf);
125 ssize_t device_store_ulong(struct device *dev, struct device_attribute *attr,
126 const char *buf, size_t count);
127 ssize_t device_show_int(struct device *dev, struct device_attribute *attr,
128 char *buf);
129 ssize_t device_store_int(struct device *dev, struct device_attribute *attr,
130 const char *buf, size_t count);
131 ssize_t device_show_bool(struct device *dev, struct device_attribute *attr,
132 char *buf);
133 ssize_t device_store_bool(struct device *dev, struct device_attribute *attr,
134 const char *buf, size_t count);
135 ssize_t device_show_string(struct device *dev, struct device_attribute *attr,
136 char *buf);
137
138 /**
139 * DEVICE_ATTR - Define a device attribute.
140 * @_name: Attribute name.
141 * @_mode: File mode.
142 * @_show: Show handler. Optional, but mandatory if attribute is readable.
143 * @_store: Store handler. Optional, but mandatory if attribute is writable.
144 *
145 * Convenience macro for defining a struct device_attribute.
146 *
147 * For example, ``DEVICE_ATTR(foo, 0644, foo_show, foo_store);`` expands to:
148 *
149 * .. code-block:: c
150 *
151 * struct device_attribute dev_attr_foo = {
152 * .attr = { .name = "foo", .mode = 0644 },
153 * .show = foo_show,
154 * .store = foo_store,
155 * };
156 */
157 #define DEVICE_ATTR(_name, _mode, _show, _store) \
158 struct device_attribute dev_attr_##_name = __ATTR(_name, _mode, _show, _store)
159
160 /**
161 * DEVICE_ATTR_PREALLOC - Define a preallocated device attribute.
162 * @_name: Attribute name.
163 * @_mode: File mode.
164 * @_show: Show handler. Optional, but mandatory if attribute is readable.
165 * @_store: Store handler. Optional, but mandatory if attribute is writable.
166 *
167 * Like DEVICE_ATTR(), but ``SYSFS_PREALLOC`` is set on @_mode.
168 */
169 #define DEVICE_ATTR_PREALLOC(_name, _mode, _show, _store) \
170 struct device_attribute dev_attr_##_name = \
171 __ATTR_PREALLOC(_name, _mode, _show, _store)
172
173 /**
174 * DEVICE_ATTR_RW - Define a read-write device attribute.
175 * @_name: Attribute name.
176 *
177 * Like DEVICE_ATTR(), but @_mode is 0644, @_show is <_name>_show,
178 * and @_store is <_name>_store.
179 */
180 #define DEVICE_ATTR_RW(_name) \
181 struct device_attribute dev_attr_##_name = __ATTR_RW(_name)
182
183 /**
184 * DEVICE_ATTR_ADMIN_RW - Define an admin-only read-write device attribute.
185 * @_name: Attribute name.
186 *
187 * Like DEVICE_ATTR_RW(), but @_mode is 0600.
188 */
189 #define DEVICE_ATTR_ADMIN_RW(_name) \
190 struct device_attribute dev_attr_##_name = __ATTR_RW_MODE(_name, 0600)
191
192 /**
193 * DEVICE_ATTR_RO - Define a readable device attribute.
194 * @_name: Attribute name.
195 *
196 * Like DEVICE_ATTR(), but @_mode is 0444 and @_show is <_name>_show.
197 */
198 #define DEVICE_ATTR_RO(_name) \
199 struct device_attribute dev_attr_##_name = __ATTR_RO(_name)
200
201 /**
202 * DEVICE_ATTR_ADMIN_RO - Define an admin-only readable device attribute.
203 * @_name: Attribute name.
204 *
205 * Like DEVICE_ATTR_RO(), but @_mode is 0400.
206 */
207 #define DEVICE_ATTR_ADMIN_RO(_name) \
208 struct device_attribute dev_attr_##_name = __ATTR_RO_MODE(_name, 0400)
209
210 /**
211 * DEVICE_ATTR_WO - Define an admin-only writable device attribute.
212 * @_name: Attribute name.
213 *
214 * Like DEVICE_ATTR(), but @_mode is 0200 and @_store is <_name>_store.
215 */
216 #define DEVICE_ATTR_WO(_name) \
217 struct device_attribute dev_attr_##_name = __ATTR_WO(_name)
218
219 /**
220 * DEVICE_ULONG_ATTR - Define a device attribute backed by an unsigned long.
221 * @_name: Attribute name.
222 * @_mode: File mode.
223 * @_var: Identifier of unsigned long.
224 *
225 * Like DEVICE_ATTR(), but @_show and @_store are automatically provided
226 * such that reads and writes to the attribute from userspace affect @_var.
227 */
228 #define DEVICE_ULONG_ATTR(_name, _mode, _var) \
229 struct dev_ext_attribute dev_attr_##_name = \
230 { __ATTR(_name, _mode, device_show_ulong, device_store_ulong), &(_var) }
231
232 /**
233 * DEVICE_INT_ATTR - Define a device attribute backed by an int.
234 * @_name: Attribute name.
235 * @_mode: File mode.
236 * @_var: Identifier of int.
237 *
238 * Like DEVICE_ULONG_ATTR(), but @_var is an int.
239 */
240 #define DEVICE_INT_ATTR(_name, _mode, _var) \
241 struct dev_ext_attribute dev_attr_##_name = \
242 { __ATTR(_name, _mode, device_show_int, device_store_int), &(_var) }
243
244 /**
245 * DEVICE_BOOL_ATTR - Define a device attribute backed by a bool.
246 * @_name: Attribute name.
247 * @_mode: File mode.
248 * @_var: Identifier of bool.
249 *
250 * Like DEVICE_ULONG_ATTR(), but @_var is a bool.
251 */
252 #define DEVICE_BOOL_ATTR(_name, _mode, _var) \
253 struct dev_ext_attribute dev_attr_##_name = \
254 { __ATTR(_name, _mode, device_show_bool, device_store_bool), &(_var) }
255
256 /**
257 * DEVICE_STRING_ATTR_RO - Define a device attribute backed by a r/o string.
258 * @_name: Attribute name.
259 * @_mode: File mode.
260 * @_var: Identifier of string.
261 *
262 * Like DEVICE_ULONG_ATTR(), but @_var is a string. Because the length of the
263 * string allocation is unknown, the attribute must be read-only.
264 */
265 #define DEVICE_STRING_ATTR_RO(_name, _mode, _var) \
266 struct dev_ext_attribute dev_attr_##_name = \
267 { __ATTR(_name, (_mode) & ~0222, device_show_string, NULL), (_var) }
268
269 #define DEVICE_ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) \
270 struct device_attribute dev_attr_##_name = \
271 __ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store)
272
273 int device_create_file(struct device *device,
274 const struct device_attribute *entry);
275 void device_remove_file(struct device *dev,
276 const struct device_attribute *attr);
277 bool device_remove_file_self(struct device *dev,
278 const struct device_attribute *attr);
279 int __must_check device_create_bin_file(struct device *dev,
280 const struct bin_attribute *attr);
281 void device_remove_bin_file(struct device *dev,
282 const struct bin_attribute *attr);
283
284 /* allows to add/remove a custom action to devres stack */
285 int devm_remove_action_nowarn(struct device *dev, void (*action)(void *), void *data);
286
287 /**
288 * devm_remove_action() - removes previously added custom action
289 * @dev: Device that owns the action
290 * @action: Function implementing the action
291 * @data: Pointer to data passed to @action implementation
292 *
293 * Removes instance of @action previously added by devm_add_action().
294 * Both action and data should match one of the existing entries.
295 */
296 static inline
devm_remove_action(struct device * dev,void (* action)(void *),void * data)297 void devm_remove_action(struct device *dev, void (*action)(void *), void *data)
298 {
299 WARN_ON(devm_remove_action_nowarn(dev, action, data));
300 }
301
302 void devm_release_action(struct device *dev, void (*action)(void *), void *data);
303
304 int __devm_add_action(struct device *dev, void (*action)(void *), void *data, const char *name);
305 #define devm_add_action(dev, action, data) \
306 __devm_add_action(dev, action, data, #action)
307
__devm_add_action_or_reset(struct device * dev,void (* action)(void *),void * data,const char * name)308 static inline int __devm_add_action_or_reset(struct device *dev, void (*action)(void *),
309 void *data, const char *name)
310 {
311 int ret;
312
313 ret = __devm_add_action(dev, action, data, name);
314 if (ret)
315 action(data);
316
317 return ret;
318 }
319 #define devm_add_action_or_reset(dev, action, data) \
320 __devm_add_action_or_reset(dev, action, data, #action)
321
322 /**
323 * devm_alloc_percpu - Resource-managed alloc_percpu
324 * @dev: Device to allocate per-cpu memory for
325 * @type: Type to allocate per-cpu memory for
326 *
327 * Managed alloc_percpu. Per-cpu memory allocated with this function is
328 * automatically freed on driver detach.
329 *
330 * RETURNS:
331 * Pointer to allocated memory on success, NULL on failure.
332 */
333 #define devm_alloc_percpu(dev, type) \
334 ((typeof(type) __percpu *)__devm_alloc_percpu((dev), sizeof(type), \
335 __alignof__(type)))
336
337 void __percpu *__devm_alloc_percpu(struct device *dev, size_t size,
338 size_t align);
339 void devm_free_percpu(struct device *dev, void __percpu *pdata);
340
341 struct device_dma_parameters {
342 /*
343 * a low level driver may set these to teach IOMMU code about
344 * sg limitations.
345 */
346 unsigned int max_segment_size;
347 unsigned int min_align_mask;
348 unsigned long segment_boundary_mask;
349 };
350
351 /**
352 * enum device_link_state - Device link states.
353 * @DL_STATE_NONE: The presence of the drivers is not being tracked.
354 * @DL_STATE_DORMANT: None of the supplier/consumer drivers is present.
355 * @DL_STATE_AVAILABLE: The supplier driver is present, but the consumer is not.
356 * @DL_STATE_CONSUMER_PROBE: The consumer is probing (supplier driver present).
357 * @DL_STATE_ACTIVE: Both the supplier and consumer drivers are present.
358 * @DL_STATE_SUPPLIER_UNBIND: The supplier driver is unbinding.
359 */
360 enum device_link_state {
361 DL_STATE_NONE = -1,
362 DL_STATE_DORMANT = 0,
363 DL_STATE_AVAILABLE,
364 DL_STATE_CONSUMER_PROBE,
365 DL_STATE_ACTIVE,
366 DL_STATE_SUPPLIER_UNBIND,
367 };
368
369 /*
370 * Device link flags.
371 *
372 * STATELESS: The core will not remove this link automatically.
373 * AUTOREMOVE_CONSUMER: Remove the link automatically on consumer driver unbind.
374 * PM_RUNTIME: If set, the runtime PM framework will use this link.
375 * RPM_ACTIVE: Run pm_runtime_get_sync() on the supplier during link creation.
376 * AUTOREMOVE_SUPPLIER: Remove the link automatically on supplier driver unbind.
377 * AUTOPROBE_CONSUMER: Probe consumer driver automatically after supplier binds.
378 * MANAGED: The core tracks presence of supplier/consumer drivers (internal).
379 * SYNC_STATE_ONLY: Link only affects sync_state() behavior.
380 * INFERRED: Inferred from data (eg: firmware) and not from driver actions.
381 */
382 #define DL_FLAG_STATELESS BIT(0)
383 #define DL_FLAG_AUTOREMOVE_CONSUMER BIT(1)
384 #define DL_FLAG_PM_RUNTIME BIT(2)
385 #define DL_FLAG_RPM_ACTIVE BIT(3)
386 #define DL_FLAG_AUTOREMOVE_SUPPLIER BIT(4)
387 #define DL_FLAG_AUTOPROBE_CONSUMER BIT(5)
388 #define DL_FLAG_MANAGED BIT(6)
389 #define DL_FLAG_SYNC_STATE_ONLY BIT(7)
390 #define DL_FLAG_INFERRED BIT(8)
391 #define DL_FLAG_CYCLE BIT(9)
392
393 /**
394 * enum dl_dev_state - Device driver presence tracking information.
395 * @DL_DEV_NO_DRIVER: There is no driver attached to the device.
396 * @DL_DEV_PROBING: A driver is probing.
397 * @DL_DEV_DRIVER_BOUND: The driver has been bound to the device.
398 * @DL_DEV_UNBINDING: The driver is unbinding from the device.
399 */
400 enum dl_dev_state {
401 DL_DEV_NO_DRIVER = 0,
402 DL_DEV_PROBING,
403 DL_DEV_DRIVER_BOUND,
404 DL_DEV_UNBINDING,
405 };
406
407 /**
408 * enum device_removable - Whether the device is removable. The criteria for a
409 * device to be classified as removable is determined by its subsystem or bus.
410 * @DEVICE_REMOVABLE_NOT_SUPPORTED: This attribute is not supported for this
411 * device (default).
412 * @DEVICE_REMOVABLE_UNKNOWN: Device location is Unknown.
413 * @DEVICE_FIXED: Device is not removable by the user.
414 * @DEVICE_REMOVABLE: Device is removable by the user.
415 */
416 enum device_removable {
417 DEVICE_REMOVABLE_NOT_SUPPORTED = 0, /* must be 0 */
418 DEVICE_REMOVABLE_UNKNOWN,
419 DEVICE_FIXED,
420 DEVICE_REMOVABLE,
421 };
422
423 /**
424 * struct dev_links_info - Device data related to device links.
425 * @suppliers: List of links to supplier devices.
426 * @consumers: List of links to consumer devices.
427 * @defer_sync: Hook to global list of devices that have deferred sync_state.
428 * @status: Driver status information.
429 */
430 struct dev_links_info {
431 struct list_head suppliers;
432 struct list_head consumers;
433 struct list_head defer_sync;
434 enum dl_dev_state status;
435 };
436
437 /**
438 * struct dev_msi_info - Device data related to MSI
439 * @domain: The MSI interrupt domain associated to the device
440 * @data: Pointer to MSI device data
441 */
442 struct dev_msi_info {
443 #ifdef CONFIG_GENERIC_MSI_IRQ
444 struct irq_domain *domain;
445 struct msi_device_data *data;
446 #endif
447 };
448
449 /**
450 * enum device_physical_location_panel - Describes which panel surface of the
451 * system's housing the device connection point resides on.
452 * @DEVICE_PANEL_TOP: Device connection point is on the top panel.
453 * @DEVICE_PANEL_BOTTOM: Device connection point is on the bottom panel.
454 * @DEVICE_PANEL_LEFT: Device connection point is on the left panel.
455 * @DEVICE_PANEL_RIGHT: Device connection point is on the right panel.
456 * @DEVICE_PANEL_FRONT: Device connection point is on the front panel.
457 * @DEVICE_PANEL_BACK: Device connection point is on the back panel.
458 * @DEVICE_PANEL_UNKNOWN: The panel with device connection point is unknown.
459 */
460 enum device_physical_location_panel {
461 DEVICE_PANEL_TOP,
462 DEVICE_PANEL_BOTTOM,
463 DEVICE_PANEL_LEFT,
464 DEVICE_PANEL_RIGHT,
465 DEVICE_PANEL_FRONT,
466 DEVICE_PANEL_BACK,
467 DEVICE_PANEL_UNKNOWN,
468 };
469
470 /**
471 * enum device_physical_location_vertical_position - Describes vertical
472 * position of the device connection point on the panel surface.
473 * @DEVICE_VERT_POS_UPPER: Device connection point is at upper part of panel.
474 * @DEVICE_VERT_POS_CENTER: Device connection point is at center part of panel.
475 * @DEVICE_VERT_POS_LOWER: Device connection point is at lower part of panel.
476 */
477 enum device_physical_location_vertical_position {
478 DEVICE_VERT_POS_UPPER,
479 DEVICE_VERT_POS_CENTER,
480 DEVICE_VERT_POS_LOWER,
481 };
482
483 /**
484 * enum device_physical_location_horizontal_position - Describes horizontal
485 * position of the device connection point on the panel surface.
486 * @DEVICE_HORI_POS_LEFT: Device connection point is at left part of panel.
487 * @DEVICE_HORI_POS_CENTER: Device connection point is at center part of panel.
488 * @DEVICE_HORI_POS_RIGHT: Device connection point is at right part of panel.
489 */
490 enum device_physical_location_horizontal_position {
491 DEVICE_HORI_POS_LEFT,
492 DEVICE_HORI_POS_CENTER,
493 DEVICE_HORI_POS_RIGHT,
494 };
495
496 /**
497 * struct device_physical_location - Device data related to physical location
498 * of the device connection point.
499 * @panel: Panel surface of the system's housing that the device connection
500 * point resides on.
501 * @vertical_position: Vertical position of the device connection point within
502 * the panel.
503 * @horizontal_position: Horizontal position of the device connection point
504 * within the panel.
505 * @dock: Set if the device connection point resides in a docking station or
506 * port replicator.
507 * @lid: Set if this device connection point resides on the lid of laptop
508 * system.
509 */
510 struct device_physical_location {
511 enum device_physical_location_panel panel;
512 enum device_physical_location_vertical_position vertical_position;
513 enum device_physical_location_horizontal_position horizontal_position;
514 bool dock;
515 bool lid;
516 };
517
518 /**
519 * struct device - The basic device structure
520 * @parent: The device's "parent" device, the device to which it is attached.
521 * In most cases, a parent device is some sort of bus or host
522 * controller. If parent is NULL, the device, is a top-level device,
523 * which is not usually what you want.
524 * @p: Holds the private data of the driver core portions of the device.
525 * See the comment of the struct device_private for detail.
526 * @kobj: A top-level, abstract class from which other classes are derived.
527 * @init_name: Initial name of the device.
528 * @type: The type of device.
529 * This identifies the device type and carries type-specific
530 * information.
531 * @mutex: Mutex to synchronize calls to its driver.
532 * @bus: Type of bus device is on.
533 * @driver: Which driver has allocated this
534 * @platform_data: Platform data specific to the device.
535 * Example: For devices on custom boards, as typical of embedded
536 * and SOC based hardware, Linux often uses platform_data to point
537 * to board-specific structures describing devices and how they
538 * are wired. That can include what ports are available, chip
539 * variants, which GPIO pins act in what additional roles, and so
540 * on. This shrinks the "Board Support Packages" (BSPs) and
541 * minimizes board-specific #ifdefs in drivers.
542 * @driver_data: Private pointer for driver specific info.
543 * @links: Links to suppliers and consumers of this device.
544 * @power: For device power management.
545 * See Documentation/driver-api/pm/devices.rst for details.
546 * @pm_domain: Provide callbacks that are executed during system suspend,
547 * hibernation, system resume and during runtime PM transitions
548 * along with subsystem-level and driver-level callbacks.
549 * @em_pd: device's energy model performance domain
550 * @pins: For device pin management.
551 * See Documentation/driver-api/pin-control.rst for details.
552 * @msi: MSI related data
553 * @numa_node: NUMA node this device is close to.
554 * @dma_ops: DMA mapping operations for this device.
555 * @dma_mask: Dma mask (if dma'ble device).
556 * @coherent_dma_mask: Like dma_mask, but for alloc_coherent mapping as not all
557 * hardware supports 64-bit addresses for consistent allocations
558 * such descriptors.
559 * @bus_dma_limit: Limit of an upstream bridge or bus which imposes a smaller
560 * DMA limit than the device itself supports.
561 * @dma_range_map: map for DMA memory ranges relative to that of RAM
562 * @dma_parms: A low level driver may set these to teach IOMMU code about
563 * segment limitations.
564 * @dma_pools: Dma pools (if dma'ble device).
565 * @dma_mem: Internal for coherent mem override.
566 * @cma_area: Contiguous memory area for dma allocations
567 * @dma_io_tlb_mem: Software IO TLB allocator. Not for driver use.
568 * @dma_io_tlb_pools: List of transient swiotlb memory pools.
569 * @dma_io_tlb_lock: Protects changes to the list of active pools.
570 * @dma_uses_io_tlb: %true if device has used the software IO TLB.
571 * @archdata: For arch-specific additions.
572 * @of_node: Associated device tree node.
573 * @fwnode: Associated device node supplied by platform firmware.
574 * @devt: For creating the sysfs "dev".
575 * @id: device instance
576 * @devres_lock: Spinlock to protect the resource of the device.
577 * @devres_head: The resources list of the device.
578 * @class: The class of the device.
579 * @groups: Optional attribute groups.
580 * @release: Callback to free the device after all references have
581 * gone away. This should be set by the allocator of the
582 * device (i.e. the bus driver that discovered the device).
583 * @iommu_group: IOMMU group the device belongs to.
584 * @iommu: Per device generic IOMMU runtime data
585 * @physical_location: Describes physical location of the device connection
586 * point in the system housing.
587 * @removable: Whether the device can be removed from the system. This
588 * should be set by the subsystem / bus driver that discovered
589 * the device.
590 *
591 * @offline_disabled: If set, the device is permanently online.
592 * @offline: Set after successful invocation of bus type's .offline().
593 * @of_node_reused: Set if the device-tree node is shared with an ancestor
594 * device.
595 * @state_synced: The hardware state of this device has been synced to match
596 * the software state of this device by calling the driver/bus
597 * sync_state() callback.
598 * @can_match: The device has matched with a driver at least once or it is in
599 * a bus (like AMBA) which can't check for matching drivers until
600 * other devices probe successfully.
601 * @dma_coherent: this particular device is dma coherent, even if the
602 * architecture supports non-coherent devices.
603 * @dma_ops_bypass: If set to %true then the dma_ops are bypassed for the
604 * streaming DMA operations (->map_* / ->unmap_* / ->sync_*),
605 * and optionall (if the coherent mask is large enough) also
606 * for dma allocations. This flag is managed by the dma ops
607 * instance from ->dma_supported.
608 * @dma_skip_sync: DMA sync operations can be skipped for coherent buffers.
609 * @dma_iommu: Device is using default IOMMU implementation for DMA and
610 * doesn't rely on dma_ops structure.
611 *
612 * At the lowest level, every device in a Linux system is represented by an
613 * instance of struct device. The device structure contains the information
614 * that the device model core needs to model the system. Most subsystems,
615 * however, track additional information about the devices they host. As a
616 * result, it is rare for devices to be represented by bare device structures;
617 * instead, that structure, like kobject structures, is usually embedded within
618 * a higher-level representation of the device.
619 */
620 struct device {
621 struct kobject kobj;
622 struct device *parent;
623
624 struct device_private *p;
625
626 const char *init_name; /* initial name of the device */
627 const struct device_type *type;
628
629 const struct bus_type *bus; /* type of bus device is on */
630 struct device_driver *driver; /* which driver has allocated this
631 device */
632 void *platform_data; /* Platform specific data, device
633 core doesn't touch it */
634 void *driver_data; /* Driver data, set and get with
635 dev_set_drvdata/dev_get_drvdata */
636 struct mutex mutex; /* mutex to synchronize calls to
637 * its driver.
638 */
639
640 struct dev_links_info links;
641 struct dev_pm_info power;
642 struct dev_pm_domain *pm_domain;
643
644 #ifdef CONFIG_ENERGY_MODEL
645 struct em_perf_domain *em_pd;
646 #endif
647
648 #ifdef CONFIG_PINCTRL
649 struct dev_pin_info *pins;
650 #endif
651 struct dev_msi_info msi;
652 #ifdef CONFIG_ARCH_HAS_DMA_OPS
653 const struct dma_map_ops *dma_ops;
654 #endif
655 u64 *dma_mask; /* dma mask (if dma'able device) */
656 u64 coherent_dma_mask;/* Like dma_mask, but for
657 alloc_coherent mappings as
658 not all hardware supports
659 64 bit addresses for consistent
660 allocations such descriptors. */
661 u64 bus_dma_limit; /* upstream dma constraint */
662 const struct bus_dma_region *dma_range_map;
663
664 struct device_dma_parameters *dma_parms;
665
666 struct list_head dma_pools; /* dma pools (if dma'ble) */
667
668 #ifdef CONFIG_DMA_DECLARE_COHERENT
669 struct dma_coherent_mem *dma_mem; /* internal for coherent mem
670 override */
671 #endif
672 #ifdef CONFIG_DMA_CMA
673 struct cma *cma_area; /* contiguous memory area for dma
674 allocations */
675 #endif
676 #ifdef CONFIG_SWIOTLB
677 struct io_tlb_mem *dma_io_tlb_mem;
678 #endif
679 #ifdef CONFIG_SWIOTLB_DYNAMIC
680 struct list_head dma_io_tlb_pools;
681 spinlock_t dma_io_tlb_lock;
682 bool dma_uses_io_tlb;
683 #endif
684 /* arch specific additions */
685 struct dev_archdata archdata;
686
687 struct device_node *of_node; /* associated device tree node */
688 struct fwnode_handle *fwnode; /* firmware device node */
689
690 #ifdef CONFIG_NUMA
691 int numa_node; /* NUMA node this device is close to */
692 #endif
693 dev_t devt; /* dev_t, creates the sysfs "dev" */
694 u32 id; /* device instance */
695
696 spinlock_t devres_lock;
697 struct list_head devres_head;
698
699 const struct class *class;
700 const struct attribute_group **groups; /* optional groups */
701
702 void (*release)(struct device *dev);
703 struct iommu_group *iommu_group;
704 struct dev_iommu *iommu;
705
706 struct device_physical_location *physical_location;
707
708 enum device_removable removable;
709
710 bool offline_disabled:1;
711 bool offline:1;
712 bool of_node_reused:1;
713 bool state_synced:1;
714 bool can_match:1;
715 #if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \
716 defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU) || \
717 defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL)
718 bool dma_coherent:1;
719 #endif
720 #ifdef CONFIG_DMA_OPS_BYPASS
721 bool dma_ops_bypass : 1;
722 #endif
723 #ifdef CONFIG_DMA_NEED_SYNC
724 bool dma_skip_sync:1;
725 #endif
726 #ifdef CONFIG_IOMMU_DMA
727 bool dma_iommu:1;
728 #endif
729 };
730
731 /**
732 * struct device_link - Device link representation.
733 * @supplier: The device on the supplier end of the link.
734 * @s_node: Hook to the supplier device's list of links to consumers.
735 * @consumer: The device on the consumer end of the link.
736 * @c_node: Hook to the consumer device's list of links to suppliers.
737 * @link_dev: device used to expose link details in sysfs
738 * @status: The state of the link (with respect to the presence of drivers).
739 * @flags: Link flags.
740 * @rpm_active: Whether or not the consumer device is runtime-PM-active.
741 * @kref: Count repeated addition of the same link.
742 * @rm_work: Work structure used for removing the link.
743 * @supplier_preactivated: Supplier has been made active before consumer probe.
744 */
745 struct device_link {
746 struct device *supplier;
747 struct list_head s_node;
748 struct device *consumer;
749 struct list_head c_node;
750 struct device link_dev;
751 enum device_link_state status;
752 u32 flags;
753 refcount_t rpm_active;
754 struct kref kref;
755 struct work_struct rm_work;
756 bool supplier_preactivated; /* Owned by consumer probe. */
757 };
758
759 #define kobj_to_dev(__kobj) container_of_const(__kobj, struct device, kobj)
760
761 /**
762 * device_iommu_mapped - Returns true when the device DMA is translated
763 * by an IOMMU
764 * @dev: Device to perform the check on
765 */
device_iommu_mapped(struct device * dev)766 static inline bool device_iommu_mapped(struct device *dev)
767 {
768 return (dev->iommu_group != NULL);
769 }
770
771 /* Get the wakeup routines, which depend on struct device */
772 #include <linux/pm_wakeup.h>
773
774 /**
775 * dev_name - Return a device's name.
776 * @dev: Device with name to get.
777 * Return: The kobject name of the device, or its initial name if unavailable.
778 */
dev_name(const struct device * dev)779 static inline const char *dev_name(const struct device *dev)
780 {
781 /* Use the init name until the kobject becomes available */
782 if (dev->init_name)
783 return dev->init_name;
784
785 return kobject_name(&dev->kobj);
786 }
787
788 /**
789 * dev_bus_name - Return a device's bus/class name, if at all possible
790 * @dev: struct device to get the bus/class name of
791 *
792 * Will return the name of the bus/class the device is attached to. If it is
793 * not attached to a bus/class, an empty string will be returned.
794 */
dev_bus_name(const struct device * dev)795 static inline const char *dev_bus_name(const struct device *dev)
796 {
797 return dev->bus ? dev->bus->name : (dev->class ? dev->class->name : "");
798 }
799
800 __printf(2, 3) int dev_set_name(struct device *dev, const char *name, ...);
801
802 #ifdef CONFIG_NUMA
dev_to_node(struct device * dev)803 static inline int dev_to_node(struct device *dev)
804 {
805 return dev->numa_node;
806 }
set_dev_node(struct device * dev,int node)807 static inline void set_dev_node(struct device *dev, int node)
808 {
809 dev->numa_node = node;
810 }
811 #else
dev_to_node(struct device * dev)812 static inline int dev_to_node(struct device *dev)
813 {
814 return NUMA_NO_NODE;
815 }
set_dev_node(struct device * dev,int node)816 static inline void set_dev_node(struct device *dev, int node)
817 {
818 }
819 #endif
820
dev_get_msi_domain(const struct device * dev)821 static inline struct irq_domain *dev_get_msi_domain(const struct device *dev)
822 {
823 #ifdef CONFIG_GENERIC_MSI_IRQ
824 return dev->msi.domain;
825 #else
826 return NULL;
827 #endif
828 }
829
dev_set_msi_domain(struct device * dev,struct irq_domain * d)830 static inline void dev_set_msi_domain(struct device *dev, struct irq_domain *d)
831 {
832 #ifdef CONFIG_GENERIC_MSI_IRQ
833 dev->msi.domain = d;
834 #endif
835 }
836
dev_get_drvdata(const struct device * dev)837 static inline void *dev_get_drvdata(const struct device *dev)
838 {
839 return dev->driver_data;
840 }
841
dev_set_drvdata(struct device * dev,void * data)842 static inline void dev_set_drvdata(struct device *dev, void *data)
843 {
844 dev->driver_data = data;
845 }
846
dev_to_psd(struct device * dev)847 static inline struct pm_subsys_data *dev_to_psd(struct device *dev)
848 {
849 return dev ? dev->power.subsys_data : NULL;
850 }
851
dev_get_uevent_suppress(const struct device * dev)852 static inline unsigned int dev_get_uevent_suppress(const struct device *dev)
853 {
854 return dev->kobj.uevent_suppress;
855 }
856
dev_set_uevent_suppress(struct device * dev,int val)857 static inline void dev_set_uevent_suppress(struct device *dev, int val)
858 {
859 dev->kobj.uevent_suppress = val;
860 }
861
device_is_registered(struct device * dev)862 static inline int device_is_registered(struct device *dev)
863 {
864 return dev->kobj.state_in_sysfs;
865 }
866
device_enable_async_suspend(struct device * dev)867 static inline void device_enable_async_suspend(struct device *dev)
868 {
869 if (!dev->power.is_prepared)
870 dev->power.async_suspend = true;
871 }
872
device_disable_async_suspend(struct device * dev)873 static inline void device_disable_async_suspend(struct device *dev)
874 {
875 if (!dev->power.is_prepared)
876 dev->power.async_suspend = false;
877 }
878
device_async_suspend_enabled(struct device * dev)879 static inline bool device_async_suspend_enabled(struct device *dev)
880 {
881 return !!dev->power.async_suspend;
882 }
883
device_pm_not_required(struct device * dev)884 static inline bool device_pm_not_required(struct device *dev)
885 {
886 return dev->power.no_pm;
887 }
888
device_set_pm_not_required(struct device * dev)889 static inline void device_set_pm_not_required(struct device *dev)
890 {
891 dev->power.no_pm = true;
892 }
893
dev_pm_syscore_device(struct device * dev,bool val)894 static inline void dev_pm_syscore_device(struct device *dev, bool val)
895 {
896 #ifdef CONFIG_PM_SLEEP
897 dev->power.syscore = val;
898 #endif
899 }
900
dev_pm_set_driver_flags(struct device * dev,u32 flags)901 static inline void dev_pm_set_driver_flags(struct device *dev, u32 flags)
902 {
903 dev->power.driver_flags = flags;
904 }
905
dev_pm_test_driver_flags(struct device * dev,u32 flags)906 static inline bool dev_pm_test_driver_flags(struct device *dev, u32 flags)
907 {
908 return !!(dev->power.driver_flags & flags);
909 }
910
dev_pm_smart_suspend(struct device * dev)911 static inline bool dev_pm_smart_suspend(struct device *dev)
912 {
913 #ifdef CONFIG_PM_SLEEP
914 return dev->power.smart_suspend;
915 #else
916 return false;
917 #endif
918 }
919
device_lock(struct device * dev)920 static inline void device_lock(struct device *dev)
921 {
922 mutex_lock(&dev->mutex);
923 }
924
device_lock_interruptible(struct device * dev)925 static inline int device_lock_interruptible(struct device *dev)
926 {
927 return mutex_lock_interruptible(&dev->mutex);
928 }
929
device_trylock(struct device * dev)930 static inline int device_trylock(struct device *dev)
931 {
932 return mutex_trylock(&dev->mutex);
933 }
934
device_unlock(struct device * dev)935 static inline void device_unlock(struct device *dev)
936 {
937 mutex_unlock(&dev->mutex);
938 }
939
DEFINE_GUARD(device,struct device *,device_lock (_T),device_unlock (_T))940 DEFINE_GUARD(device, struct device *, device_lock(_T), device_unlock(_T))
941
942 static inline void device_lock_assert(struct device *dev)
943 {
944 lockdep_assert_held(&dev->mutex);
945 }
946
dev_has_sync_state(struct device * dev)947 static inline bool dev_has_sync_state(struct device *dev)
948 {
949 if (!dev)
950 return false;
951 if (dev->driver && dev->driver->sync_state)
952 return true;
953 if (dev->bus && dev->bus->sync_state)
954 return true;
955 return false;
956 }
957
dev_set_removable(struct device * dev,enum device_removable removable)958 static inline void dev_set_removable(struct device *dev,
959 enum device_removable removable)
960 {
961 dev->removable = removable;
962 }
963
dev_is_removable(struct device * dev)964 static inline bool dev_is_removable(struct device *dev)
965 {
966 return dev->removable == DEVICE_REMOVABLE;
967 }
968
dev_removable_is_valid(struct device * dev)969 static inline bool dev_removable_is_valid(struct device *dev)
970 {
971 return dev->removable != DEVICE_REMOVABLE_NOT_SUPPORTED;
972 }
973
974 /*
975 * High level routines for use by the bus drivers
976 */
977 int __must_check device_register(struct device *dev);
978 void device_unregister(struct device *dev);
979 void device_initialize(struct device *dev);
980 int __must_check device_add(struct device *dev);
981 void device_del(struct device *dev);
982
983 DEFINE_FREE(device_del, struct device *, if (_T) device_del(_T))
984
985 int device_for_each_child(struct device *parent, void *data,
986 device_iter_t fn);
987 int device_for_each_child_reverse(struct device *parent, void *data,
988 device_iter_t fn);
989 int device_for_each_child_reverse_from(struct device *parent,
990 struct device *from, void *data,
991 device_iter_t fn);
992 struct device *device_find_child(struct device *parent, const void *data,
993 device_match_t match);
994 /**
995 * device_find_child_by_name - device iterator for locating a child device.
996 * @parent: parent struct device
997 * @name: name of the child device
998 *
999 * This is similar to the device_find_child() function above, but it
1000 * returns a reference to a device that has the name @name.
1001 *
1002 * NOTE: you will need to drop the reference with put_device() after use.
1003 */
device_find_child_by_name(struct device * parent,const char * name)1004 static inline struct device *device_find_child_by_name(struct device *parent,
1005 const char *name)
1006 {
1007 return device_find_child(parent, name, device_match_name);
1008 }
1009
1010 /**
1011 * device_find_any_child - device iterator for locating a child device, if any.
1012 * @parent: parent struct device
1013 *
1014 * This is similar to the device_find_child() function above, but it
1015 * returns a reference to a child device, if any.
1016 *
1017 * NOTE: you will need to drop the reference with put_device() after use.
1018 */
device_find_any_child(struct device * parent)1019 static inline struct device *device_find_any_child(struct device *parent)
1020 {
1021 return device_find_child(parent, NULL, device_match_any);
1022 }
1023
1024 int device_rename(struct device *dev, const char *new_name);
1025 int device_move(struct device *dev, struct device *new_parent,
1026 enum dpm_order dpm_order);
1027 int device_change_owner(struct device *dev, kuid_t kuid, kgid_t kgid);
1028
device_supports_offline(struct device * dev)1029 static inline bool device_supports_offline(struct device *dev)
1030 {
1031 return dev->bus && dev->bus->offline && dev->bus->online;
1032 }
1033
1034 #define __device_lock_set_class(dev, name, key) \
1035 do { \
1036 struct device *__d2 __maybe_unused = dev; \
1037 lock_set_class(&__d2->mutex.dep_map, name, key, 0, _THIS_IP_); \
1038 } while (0)
1039
1040 /**
1041 * device_lock_set_class - Specify a temporary lock class while a device
1042 * is attached to a driver
1043 * @dev: device to modify
1044 * @key: lock class key data
1045 *
1046 * This must be called with the device_lock() already held, for example
1047 * from driver ->probe(). Take care to only override the default
1048 * lockdep_no_validate class.
1049 */
1050 #ifdef CONFIG_LOCKDEP
1051 #define device_lock_set_class(dev, key) \
1052 do { \
1053 struct device *__d = dev; \
1054 dev_WARN_ONCE(__d, !lockdep_match_class(&__d->mutex, \
1055 &__lockdep_no_validate__), \
1056 "overriding existing custom lock class\n"); \
1057 __device_lock_set_class(__d, #key, key); \
1058 } while (0)
1059 #else
1060 #define device_lock_set_class(dev, key) __device_lock_set_class(dev, #key, key)
1061 #endif
1062
1063 /**
1064 * device_lock_reset_class - Return a device to the default lockdep novalidate state
1065 * @dev: device to modify
1066 *
1067 * This must be called with the device_lock() already held, for example
1068 * from driver ->remove().
1069 */
1070 #define device_lock_reset_class(dev) \
1071 do { \
1072 struct device *__d __maybe_unused = dev; \
1073 lock_set_novalidate_class(&__d->mutex.dep_map, "&dev->mutex", \
1074 _THIS_IP_); \
1075 } while (0)
1076
1077 void lock_device_hotplug(void);
1078 void unlock_device_hotplug(void);
1079 int lock_device_hotplug_sysfs(void);
1080 int device_offline(struct device *dev);
1081 int device_online(struct device *dev);
1082
1083 void set_primary_fwnode(struct device *dev, struct fwnode_handle *fwnode);
1084 void set_secondary_fwnode(struct device *dev, struct fwnode_handle *fwnode);
1085 void device_set_node(struct device *dev, struct fwnode_handle *fwnode);
1086 int device_add_of_node(struct device *dev, struct device_node *of_node);
1087 void device_remove_of_node(struct device *dev);
1088 void device_set_of_node_from_dev(struct device *dev, const struct device *dev2);
1089
dev_of_node(struct device * dev)1090 static inline struct device_node *dev_of_node(struct device *dev)
1091 {
1092 if (!IS_ENABLED(CONFIG_OF) || !dev)
1093 return NULL;
1094 return dev->of_node;
1095 }
1096
dev_num_vf(struct device * dev)1097 static inline int dev_num_vf(struct device *dev)
1098 {
1099 if (dev->bus && dev->bus->num_vf)
1100 return dev->bus->num_vf(dev);
1101 return 0;
1102 }
1103
1104 /*
1105 * Root device objects for grouping under /sys/devices
1106 */
1107 struct device *__root_device_register(const char *name, struct module *owner);
1108
1109 /* This is a macro to avoid include problems with THIS_MODULE */
1110 #define root_device_register(name) \
1111 __root_device_register(name, THIS_MODULE)
1112
1113 void root_device_unregister(struct device *root);
1114
dev_get_platdata(const struct device * dev)1115 static inline void *dev_get_platdata(const struct device *dev)
1116 {
1117 return dev->platform_data;
1118 }
1119
1120 /*
1121 * Manual binding of a device to driver. See drivers/base/bus.c
1122 * for information on use.
1123 */
1124 int __must_check device_driver_attach(const struct device_driver *drv,
1125 struct device *dev);
1126 int __must_check device_bind_driver(struct device *dev);
1127 void device_release_driver(struct device *dev);
1128 int __must_check device_attach(struct device *dev);
1129 int __must_check driver_attach(const struct device_driver *drv);
1130 void device_initial_probe(struct device *dev);
1131 int __must_check device_reprobe(struct device *dev);
1132
1133 bool device_is_bound(struct device *dev);
1134
1135 /*
1136 * Easy functions for dynamically creating devices on the fly
1137 */
1138 __printf(5, 6) struct device *
1139 device_create(const struct class *cls, struct device *parent, dev_t devt,
1140 void *drvdata, const char *fmt, ...);
1141 __printf(6, 7) struct device *
1142 device_create_with_groups(const struct class *cls, struct device *parent, dev_t devt,
1143 void *drvdata, const struct attribute_group **groups,
1144 const char *fmt, ...);
1145 void device_destroy(const struct class *cls, dev_t devt);
1146
1147 int __must_check device_add_groups(struct device *dev,
1148 const struct attribute_group **groups);
1149 void device_remove_groups(struct device *dev,
1150 const struct attribute_group **groups);
1151
device_add_group(struct device * dev,const struct attribute_group * grp)1152 static inline int __must_check device_add_group(struct device *dev,
1153 const struct attribute_group *grp)
1154 {
1155 const struct attribute_group *groups[] = { grp, NULL };
1156
1157 return device_add_groups(dev, groups);
1158 }
1159
device_remove_group(struct device * dev,const struct attribute_group * grp)1160 static inline void device_remove_group(struct device *dev,
1161 const struct attribute_group *grp)
1162 {
1163 const struct attribute_group *groups[] = { grp, NULL };
1164
1165 device_remove_groups(dev, groups);
1166 }
1167
1168 int __must_check devm_device_add_group(struct device *dev,
1169 const struct attribute_group *grp);
1170
1171 /*
1172 * get_device - atomically increment the reference count for the device.
1173 *
1174 */
1175 struct device *get_device(struct device *dev);
1176 void put_device(struct device *dev);
1177
1178 DEFINE_FREE(put_device, struct device *, if (_T) put_device(_T))
1179
1180 bool kill_device(struct device *dev);
1181
1182 #ifdef CONFIG_DEVTMPFS
1183 int devtmpfs_mount(void);
1184 #else
devtmpfs_mount(void)1185 static inline int devtmpfs_mount(void) { return 0; }
1186 #endif
1187
1188 /* drivers/base/power/shutdown.c */
1189 void device_shutdown(void);
1190
1191 /* debugging and troubleshooting/diagnostic helpers. */
1192 const char *dev_driver_string(const struct device *dev);
1193
1194 /* Device links interface. */
1195 struct device_link *device_link_add(struct device *consumer,
1196 struct device *supplier, u32 flags);
1197 void device_link_del(struct device_link *link);
1198 void device_link_remove(void *consumer, struct device *supplier);
1199 void device_links_supplier_sync_state_pause(void);
1200 void device_links_supplier_sync_state_resume(void);
1201 void device_link_wait_removal(void);
1202
1203 /* Create alias, so I can be autoloaded. */
1204 #define MODULE_ALIAS_CHARDEV(major,minor) \
1205 MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
1206 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \
1207 MODULE_ALIAS("char-major-" __stringify(major) "-*")
1208
1209 #endif /* _DEVICE_H_ */
1210